Security readout for executives and security teams
Plain-English summary
CVE-2026-4046 is an availability flaw in GNU glibc iconv. An application that converts untrusted input using IBM1390 or IBM1399 character sets may crash. This is a denial-of-service risk, not a data theft or code execution issue based on the provided sources.
Executive priority
Treat as high priority for availability-sensitive and internet-facing systems. The business risk is service disruption, especially in systems that parse external content. Patch or disable unused character sets through normal emergency-change processes.
Technical view
glibc iconv in versions 2.43 and earlier can hit an assertion failure during IBM1390 or IBM1399 conversion, mapped to CWE-617. The CVSS 3.1 score is 7.5 because the reported impact is network-reachable, unauthenticated, low-complexity availability loss.
Likely exposure
Exposure is most likely where Linux services use glibc iconv on attacker-controlled content or attacker-selected encodings and IBM1390/IBM1399 converters are installed. Systems not using those character sets have a straightforward mitigation path.
Exploitation context
The bundle does not show CISA KEV listing or cited evidence of active exploitation. The stated risk is remote application crash when a reachable application processes untrusted input through the affected character set conversions.
Researcher notes
The source bundle has inconsistent affected-version metadata, but the description and glibc advisory state versions 2.43 and earlier. No exploit code, patch diff analysis, or active exploitation evidence is included here.
Mitigation direction
- Check GNU glibc and operating-system vendor advisories for fixed packages.
- Remove IBM1390 and IBM1399 character sets where they are not needed.
- Prioritize internet-facing services that process uploaded text, mail, documents, or user-selected encodings.
- Apply vendor updates after compatibility testing.
- Review Siemens advisory if affected Siemens products are in scope.
Validation and detection
- Inventory glibc versions on Linux servers and appliances.
- Check whether IBM1390 or IBM1399 conversion modules are installed or enabled.
- Identify applications calling iconv on untrusted input or user-selected encodings.
- Confirm vendor patches or charset removal in staging before production rollout.
- Review service logs for unexplained assertion failures or crashes in text conversion paths.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-617: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-4046 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://sourceware.org/bugzilla/show_bug.cgi?id=33980CVE reference, glibc · issue-tracking
- https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0007;hb=HEADCVE reference, glibc · vendor-advisory
- https://inbox.sourceware.org/libc-announce/76814edf-cf7f-47ec-979d-2dce0a2c76bf@gotplt.org/T/#uCVE reference, glibc · mailing-list
- https://cert-portal.siemens.com/productcert/html/ssa-082556.htmlCVE reference, siemens-SADP
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Reachable Assertion
Reachable Assertion represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.